JP2016215146A - Gas-liquid separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas-liquid separator that can be installed even in a narrow place such as a vehicle engine room and is high in collection efficiency.SOLUTION: In a gas-liquid separator of a system in which a mixed fluid of liquid and gas is collided with an internal wall face of a separating container, thereby separating liquid and gas, the inside of the separating container is in the form of a spiral passage, and the internal wall face of the spiral passage is a wall face with which the mixed fluid of gas and liquid comes into contact. A gas outlet pipe is connected to the upper face of the separating container. The lower face side of the separating container has an inclined bottom face part for collecting liquid droplets separated in the spiral passage. A liquid recovery tank is connected, via a liquid outlet pipe (exhaust liquid pipe), to a liquid collection part continuous with the inclined bottom face part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas-liquid separator that separates liquid and gas from a mixed fluid containing liquid (water, etc.) and gas (air, gas, etc.).

  For example, an EGR (Exhaust Gas Recirculation) system is known as one of systems (devices) for purifying exhaust gas from an internal combustion engine. In the EGR system, by cooling the EGR gas that is recirculated into the combustion chamber, the combustion temperature can be lowered, thereby reducing the amount of NOx (nitrogen oxide) emissions. When the EGR gas is cooled, moisture contained in the EGR gas is condensed and condensed water is generated in the EGR flow path. In an environment where the outside air temperature is 0 ° C. or less, condensed water is more likely to be generated.

  Since EGR gas contains sulfur in the fuel, the condensed water in the EGR flow path contains sulfuric acid. If this condensed water containing sulfuric acid adheres to or stays in the EGR flow path or the combustion chamber of the internal combustion engine, etc., each part of the internal combustion engine (EGR flow path, EGR valve, intake flow path, combustion chamber, etc.) is corroded or damaged, etc. It is thought to cause. It is also conceivable that the combustion chamber of the internal combustion engine sucks in a large amount of condensed water, thereby causing damage to the internal combustion engine due to a so-called water hammer.

  Therefore, a gas-liquid separator (or a gas-water separator), a water absorbing material (filter), or the like is used to remove condensed water from the EGR gas. As the gas-liquid separator, for example, a cyclone type gas-liquid separator is known. This cyclone type gas-liquid separator is a system that separates liquid and gas by introducing a gas containing liquid in a tangential direction into the separation cylinder, and forming a swirl flow in the separation cylinder. In general, the separated liquid is discharged from the lower part of the separation cylinder and only the gas is taken out from the upper part of the separation cylinder. In addition, there has also been proposed a barrier provided in the separation cylinder for suppressing the rotation of the separation liquid in order to enhance the separation performance by promoting the discharge of the separation liquid from the separation cylinder (see Patent Document 1). Furthermore, the condensate collecting part which collects the condensate produced from EGR gas by the uneven | corrugated | grooved part provided in the inner wall of the EGR gas flow path of the EGR gas flow downstream is provided, and it collected by this condensate collection part An EGR device that stores and stores condensed water in a storage section has also been proposed (see Patent Document 2). For example, an exhaust gas recirculation device (see Patent Document 3) in which a water absorbing material is provided on a foreign matter collecting filter that protrudes from the inner wall surface of the exhaust pipe into the exhaust gas flow path is known as a device that employs a water absorbing material or a filter. It has been.

JP-A-9-220421 JP 2013-29081 A JP 2012-202265 A

However, the conventional gas-liquid separation means described above has the following drawbacks.
That is, a cyclone type gas-liquid separation device or an EGR gas flow path that separates liquid and gas by introducing gas containing liquid into the separation cylinder in a tangential direction and forming a swirl flow in the separation cylinder In the case of an apparatus for gas-liquid separation with a built-in condensed water collecting part, the moisture collecting action is limited, and it cannot cope with a wide range of gas flow rates such as a flow rate of 10 to 100 m / s. Furthermore, there is little empty space in the vehicle engine room, and it is difficult to install a relatively large gas-liquid separator such as a cyclone system. Further, in the case of an exhaust gas recirculation device, a separation member such as a filter or a water absorbing material is disposed in the separation container, so that the ventilation resistance is high and the ventilation resistance is increased even in a region where there is a large amount of air and a high flow velocity. On the other hand, a load is applied, resulting in deterioration of fuel consumption.

  The present invention has been made in order to eliminate the disadvantages of the conventional gas-liquid separation means described above. By eliminating the separation member such as a filter and a water-absorbing material and reducing the air flow resistance, the flow rate is 10 to 100 m / s. Thus, the present invention is intended to provide a gas-liquid separation device that can cope with a wide range of gas flow rates as described above and can be installed in a narrow place such as an engine room of a vehicle and has high collection efficiency.

  The gas-liquid separation device according to the present invention introduces a liquid-gas mixed fluid (hereinafter referred to as “gas-liquid mixed fluid” for convenience of description) into the separation container in a tangential direction, and causes a swirl flow in the separation container. A gas-liquid separation device of a type that separates the liquid and gas by forming the inside of the separation container into a spiral channel and contacting the inner wall surface of the spiral channel with the gas-liquid mixed fluid A gas outlet pipe protruding from the central portion of the spiral flow path is connected to the upper surface side of the separation container on the upper surface side of the separation container, and the lower surface side of the separation container is separated in the spiral flow path It has an inclined bottom part for collecting droplets, and a liquid recovery tank is connected to a liquid collecting part connected to the inclined bottom part via a liquid outlet pipe (drainage pipe). is there.

  In addition, the apparatus of the present invention preferably has a rough surface on the inner wall surface of the spiral flow path of the separation container that forms the contact wall surface of the gas-liquid mixed fluid.

  The gas-liquid separation device of the present invention eliminates a separation member such as a filter and a water absorbing material in the gas-liquid separation container so as to reduce the ventilation resistance, and makes the gas-liquid mixed fluid contact the inner wall surface of the spiral channel. By increasing the wall contact length of the gas-liquid mixed fluid as a method of gas-liquid separation, the gas-liquid mixed fluid flows over a long distance while contacting the inner wall surface of the spiral flow path, and friction with the inner wall surface Gas-liquid separation is more effectively performed, and not only miniaturization of the apparatus can be achieved, but also a wide range of gas flow rates such as a flow rate of 10 to 100 m / s can be sufficiently handled, thereby improving the fuel efficiency of the internal combustion engine. Also has a great effect. In addition, by providing a liquid recovery tank at the bottom of the separation vessel via a liquid outlet pipe, the collected droplets are prevented from being rolled up into the separation vessel, and the drop in the droplet collection rate at high flow rates is suppressed. it can. Furthermore, by making the contact wall surface of the gas-liquid mixed fluid in the spiral flow path rough, it is possible to efficiently form droplets by surface collision and increase the collection efficiency of the droplets. .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a first embodiment of a gas-liquid separation device according to the present invention with an open lid (with an upper lid removed). It is a front view of the gas-liquid separator shown in FIG. FIG. 3 is a longitudinal sectional front view of the gas-liquid separator shown in FIGS. 1 and 2. It is a perspective view which opens and shows the 2nd Example of the gas-liquid separator which concerns on this invention (state which removed the upper cover). It is a vertical front view of the gas-liquid separator shown in FIG. 4 and 5 exemplify a rough surface applied to the spiral flow path of the gas-liquid separation device shown in FIGS. 4 and 5, (a) shows an uneven lattice arrangement, and (b) shows an uneven rhombus arrangement, respectively. Show.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 6, 1 and 11 are gas-liquid separation devices, 2 and 12 are gas-liquid separation containers, 2-1 and 12-1 are spiral channels, 2-2 is a contact wall surface of the gas-liquid mixed fluid, 12-2 is a rough contact surface of the gas-liquid mixed fluid, 2-3 and 12-3 are inclined bottom surfaces, 2-4 and 12-4 are liquid collecting portions, 2-5 and 12-5 are upper lids, 3 , 13 are gas-liquid mixed fluid inlet pipes, 3-1, 13-1 are end openings, 4, 14 are gas outlet pipes, 5, 15 are liquid outlet pipes, 6, 16 are liquid recovery tanks (water storage tanks, etc.) ), 7 and 17 are liquid discharge pipes.

A gas-liquid separation device 1 according to the first embodiment of the present invention shown in FIGS. 1 to 3 includes a gas-liquid separation container 2 having a spiral flow channel 2-1 formed by a spiral wall surface, and a gas-liquid separation container. The gas-liquid mixed fluid inlet pipe 3 connected in the tangential direction to the outermost flow path of the two spiral flow paths 2-1 and the upper surface of the gas-liquid separation container 2 are vertically connected through the upper lid 2-5. The gas outlet pipe 4 and the liquid recovery tank 6 connected to the bottom surface of the gas-liquid separation container 2 are configured. The spiral flow path 2-1 of the gas-liquid separation container 2 is configured such that the gas-liquid mixed fluid contact wall surface 2 contacts the inner wall surface (wall surface on the spiral center side) with which the gas-liquid mixed fluid flowing in from the gas-liquid mixed fluid inlet pipe 3 contacts. 2 and a mortar-shaped inclined bottom surface portion 2-3 connected to the lower end edge of the outermost contact wall surface 2-2 is formed below the spiral flow channel 2-1, and the inclined bottom surface portion 2- A liquid recovery tank 6 is connected via a liquid outlet pipe 5 to a cylindrical liquid collecting part 2-4 provided at a substantially central part of 3.
Here, the gas-liquid separation container 2 is configured by the spiral flow channel 2-1. For example, in the cyclone type, the fluid contacts the wall surface located on the outermost periphery, but the gas-liquid mixed fluid flow channel is formed in a spiral shape. As a result, the contact wall length of the fluid is increased, and the gas-liquid separation of the gas-liquid mixed fluid is more effectively performed due to friction with the contact wall surface (moisture becomes easier to form water droplets or droplets). To get.
The upper lid 2-5 is detachably fixed to the upper surface portion of the gas-liquid separation container 2 with screws, bolts, nuts or the like.

  The gas-liquid mixed fluid inlet pipe 3 connected in a tangential direction to the outermost flow path of the spiral flow path 2-1 of the gas-liquid separation container 2 has an end opening 3-1 of the gas-liquid separation container 2. It is connected to the outermost channel inlet of the spiral channel 2-1. On the other hand, the gas outlet pipe 4 has an upper lid so that it is perpendicular to the substantially central portion of the upper surface of the gas-liquid separation container 2 (the end portion of the spiral flow path) and the lower end opening projects into the gas-liquid separation container 2. It is vertically connected through 2-5. In addition, although it does not specifically limit as protrusion length (protrusion allowance) of the protrusion part 4-1 in the gas-liquid separation container 2 of the gas exit pipe | tube 4, Although 5-20 mm is preferable. That is, if the protrusion length is less than 5 mm, the effect of suppressing the suction of the liquid droplets from the gas outlet pipe 4 is small, while if it exceeds 20 mm, the liquid collection to the drain pipe 5 side is suppressed.

  A liquid recovery tank 6 is connected to a cylindrical liquid collecting portion 2-4 provided at a substantially central portion of the inclined bottom surface portion 2-3 of the gas-liquid separation container 2 via a liquid outlet pipe 5.

  A moderately sized space S is provided between the lower end of the contact wall surface 2-1 at the center of the gas-liquid separation container 2 and the inclined bottom surface 2-3 as shown in FIG.

  1 to 3, the gas-liquid mixed fluid M that has flowed into the gas-liquid separation container 2 from the gas-liquid mixed fluid inlet pipe 3 flows into the spiral flow path 2 of the gas-liquid separation container 2. The gas-liquid mixed fluid flows over a long distance while contacting the inner wall surface of the spiral channel, and gas-liquid separation by friction with the inner wall surface is effective. To be done. That is, the gas-liquid mixed fluid M is effectively separated into the gas G and the droplet W by colliding with or contacting the contact wall surface 2-2 by the centrifugal force or inertial force acting while flowing through the spiral flow path. Is done. The separated droplet W in the gas-liquid mixed fluid M adheres to the contact wall surface 2-2, and then grows and grows greatly by being combined with other droplets while descending the wall surface by the action of its own weight and airflow. The liquid falls on the bottom surface part 2-3 and flows downward, and is collected as a liquid in a cylindrical liquid collecting part 2-4 provided at a substantially central part of the inclined bottom surface part 2-3. The liquid collected in the liquid collection unit 2-4 is collected in the liquid collection tank 6 through the liquid outlet pipe 5. The liquid droplets W thus separated from the gas-liquid mixed fluid M are collected in a liquid collection tank 6 that is separate from the gas-liquid separation container 2, whereby the collected liquid droplets into the gas-liquid separation container 2 are collected. Winding up is prevented, and a decrease in liquid collection rate in a high flow rate region can be suppressed. The liquid collected in the liquid recovery tank 6 is discharged by the liquid discharge pipe 7. On the other hand, the separated gas G in the gas-liquid mixed fluid M flows out from the gas outlet pipe 4 on the upper surface of the gas-liquid separation container 2. In addition, by appropriately setting the protrusion length of the protrusion 4-1 in the gas-liquid separation container 2 of the gas outlet pipe 4 in consideration of the effect of suppressing droplet suction as described above, the droplet W Only the separated gas G can be effectively taken out without being sucked.

Next, the gas-liquid separation device 11 according to the second embodiment of the present invention shown in FIGS. 4 to 5 has a contact wall 2-2 of the gas-liquid separation container shown in FIGS. Except for 12-2, it has the same configuration as the gas-liquid separator having the configuration shown in FIGS.
That is, the structure is similar to the gas-liquid separator 1 of the present invention shown in FIGS. 1 to 3, and the gas-liquid separator 11 has a spiral flow path 12-1 formed by a spiral wall surface. The liquid separation container 12, the gas-liquid mixed fluid inlet pipe 13 tangentially connected to the outermost flow path of the spiral flow path 12-1 of the gas-liquid separation container 12, and the upper lid 12 on the upper surface of the gas-liquid separation container 12 The gas outlet pipe 14 is connected vertically through the −5 and the liquid recovery tank 16 connected to the bottom surface of the gas-liquid separation container 12. The spiral flow path 12-1 of the gas-liquid separation container 12 has an inner wall surface (wall surface on the spiral center side) in contact with the gas-liquid mixed fluid flowing in from the gas-liquid mixed fluid inlet pipe 13 as a rough surface of the gas-liquid mixed fluid. While forming the contact wall surface 12-2, a mortar-shaped inclined bottom surface portion 12-3 connected to the lower end edge of the outermost rough contact wall surface 12-2 is formed below the spiral flow path 12-1. A liquid recovery tank 16 is connected via a liquid outlet pipe 15 to a cylindrical liquid collecting portion 12-4 provided at a substantially central portion of the inclined bottom surface portion 12-3. 12-5 is an upper lid, 13-1 is an end opening, and 14-1 is a protrusion in the gas-liquid separation container 12 of the gas outlet pipe 14.

  In the apparatus of the second embodiment, the contact wall surface of the gas-liquid mixed fluid is a rough contact wall surface 12-2 by making it easy for the droplet particles in the gas-liquid mixed fluid to adhere to the contact wall surface. This is to improve the gas-liquid separation efficiency in the gas-liquid separator and increase the amount of droplets collected from the gas-liquid mixed fluid. Here, the rough surface is such a roughness that the droplet particles are easily caught on the surface and do not hinder the flow of the airflow. For example, when the particle size of the droplet particles in the gas-liquid mixed fluid is a mixed fluid of several μm to several hundred μm, the difference between the concave and convex portions on the surface of the contact wall surface 12-1 is about several hundred μm to 5 mm. It is desirable to improve the collection rate of the droplets by performing a surface treatment (irregularity formation). This numerical value varies depending on the flow velocity of the gas-liquid mixed fluid, the type of liquid droplet (water droplet, oil droplet, etc.), the internal shape of the gas-liquid separation container 12, and the like, and is not limited to the above numerical value. The rough contact wall surface 12-2 may be formed by providing a material that easily attaches droplets to the surface, instead of the surface treatment. For example, a woven fabric or a net-like mesh (mesh) woven with metal fibers such as stainless steel may be attached, and if conditions such as heat resistance and corrosion resistance are satisfied, synthetic resin, ceramic, etc. It may be. Examples of the rough surface include an uneven lattice arrangement shown in FIG. 6A and an uneven rhombus arrangement shown in FIG. 6B.

  Also in the gas-liquid separator 11 having the configuration shown in FIGS. 4 to 5, in the gas-liquid separation container 12 through the gas-liquid mixed fluid inlet pipe 13, similarly to the gas-liquid separator 1 having the configuration shown in FIGS. 1 to 3. The gas-liquid mixed fluid M flowing into the gas moves while swirling along the spiral flow path 12-1 of the gas-liquid separation container 12. At this time, the gas-liquid mixed fluid moves within the rough surface of the spiral flow path. A long distance flows while contacting the wall surface, that is, the rough contact wall surface 12-2, and gas-liquid separation by friction with the rough contact wall surface 12-2 is more effectively performed. That is, the gas-liquid mixed fluid M is effectively separated into the gas G and the droplet W by colliding with or contacting the contact wall surface 12-2 due to the centrifugal force or inertial force acting while flowing through the spiral channel. However, in the case of the rough contact surface 12-2, the separation of the droplet W from the gas-liquid mixed fluid M is further promoted by the action of the rough surface as described above. The separated droplet W in the gas-liquid mixed fluid M adheres to the contact wall surface 12-2, and then grows and tilts greatly by combining with other droplets while descending the wall surface by the action of its own weight and airflow. The liquid falls on the bottom surface portion 12-3 and flows downward, and is collected as a liquid in a cylindrical liquid collecting portion 12-4 provided at a substantially central portion of the inclined bottom surface portion 12-3. The liquid collected in the liquid collection unit 12-4 is collected in the liquid collection tank 16 through the liquid outlet pipe 15.

  Also in the case of the apparatus of the present embodiment, the droplet W separated from the gas-liquid mixed fluid M is collected in the liquid collection tank 16 provided separately from the gas-liquid separation container 12, thereby Needless to say, the winding into the liquid separation container 12 is prevented, and the decrease in the liquid collection rate in the high flow rate region can be suppressed. On the other hand, the separated gas G in the gas-liquid mixed fluid M flows out from the gas outlet pipe 14 on the upper surface of the gas-liquid separation container 12, but also in this embodiment, the gas-liquid separation container of the gas outlet pipe 14 is used. 12 by appropriately setting the projecting length of the projecting portion 14-1 in the above in consideration of the effect of suppressing the suction of the liquid droplets as described above, so that only the gas G separated without sucking the liquid droplets W can be obtained. Needless to say, it can be taken out effectively.

DESCRIPTION OF SYMBOLS 1, 11 Gas-liquid separation apparatus 2, 12 Gas-liquid separation container 2-1, 12-1 Spiral flow path 2-2 Contact wall surface of gas-liquid mixed fluid 12-2 Contact wall surface of rough surface of gas-liquid mixed fluid 2- 3, 12-3 Inclined bottom part 2-4, 12-4 Liquid collecting part 2-5, 12-5 Upper lid 3, 13 Gas-liquid mixed fluid inlet pipe 3-1, 13-1 End opening part 4, 14 Gas Outlet pipe 4-1, 14-1 Protrusion 5,15 Liquid outlet pipe 6,16 Liquid recovery tank 7,17 Liquid discharge pipe M Gas-liquid mixed fluid W Droplet G Gas S Space

Claims (2)

  A gas-liquid separator of a type that separates the liquid and gas by introducing a fluid mixture of liquid and gas into the separation container in a tangential direction and forming a swirl flow in the separation container. And the inner wall surface of the spiral flow channel as a contact wall surface of the gas-liquid mixed fluid, and an opening protrudes from the upper surface side of the separation container at the center of the spiral flow channel A gas outlet pipe is connected to the lower surface of the separation container, and has an inclined bottom surface portion for collecting droplets separated in the spiral flow path, and a liquid outlet pipe ( A gas-liquid separator characterized in that a liquid recovery tank is connected via a drainage pipe).   The gas-liquid separator according to claim 1, wherein a contact wall surface of the gas-liquid mixed fluid is a rough surface.

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